TOKYO (Nikkei)–Keio Corp. (9008), Daido Steel Co. (5471) and a bevy of other Japanese firms are investing in energy-saving technologies from a long-term perspective as the specter of a full shutdown of the country’s nuclear power plants looms large.

Railway operator Keio on Feb. 23 started operating a train that uses only LED lighting. It replaced conventional fluorescent lighting on a mainstay 8,000 series train running between Shinjuku and major hub Keio Hachioji. Not only will this reduce power consumption 35%, but it will also extend the replacement cycle, the company says. At the end of next month, it will also install LED lights on an Inokashira-line train in downtown Tokyo.

Central Japan Railway Co. (9022) will retire all 300 series cars on its Tokkaido Shinkansen bullet train line. The new cars will cut fuel consumption 25%, according to the firm.

Retailers are spearheading the switch to LED lighting. Supermarket chain operator Uny Co. (8270) introduced LED technology at all the stores it renovated or opened this fiscal year. The revamped Piago Kanie outlet, which reopened in September as an environmentally friendly showcase, sports not only LED lights but solar panels and an air conditioning system that uses geothermal heat as well.

Seven & i Holdings Co.’s (3382) convenience store unit, Seven-Eleven Japan Co., spent a total of 20 billion yen in the year ending February 29 to install LED lights at around 10,000 stores, or more than 70% of its domestic network. Lawson Inc. (2651) has adopted the lights at almost all of its 10,000 convenience stores, while FamilyMart Co. (8028) is progressing with plans to have them in 4,000 sites, or half its locations.

Meanwhile, NEC Corp. (6701) seeks to reduce the amount of energy used by roughly 24,000 personal computers. It has adopted its own EnePal PC service, which automatically monitors and controls the power consumption of PCs, at about 80 domestic locations, including its headquarters, offices and branches. This is expected to pare the PCs average power consumption by 20%.

Daido Steel’s Chita plant in Aichi Prefecture consumes the most electricity of any factory serviced by Chubu Electric Power Co. (9502), which shut down a nuclear facility at the request of the government last year. The steelmaker last summer throttled down the plant’s electric furnace during daytime shifts on Tuesdays and Wednesdays — when automakers were operating — a move that helped save around 100,000kw.

Over the next two years, Daido Steel will spend 20 billion yen to rebuild the Chita plant. Much of the investment will go toward installing a large electric furnace that can use natural gas and other forms of alternative energy. The new furnace will begin operating as soon as fall 2013 and is being counted on to drastically cut electricity use.

Panasonic Corp. (6752) last year embarked on a power conservation drive, which included detailed evaluations of its electricity use, at 16 factories, mostly in eastern Japan. It deployed sensors to show how much energy and gas was being used by each piece of equipment to optimize operations and minimize infrastructure. As a result, it succeeded in maintaining production volumes while slashing peak power use 15%. The company says its electricity bill during that time was down around 10% on the year, saving it as much as 250 million yen. The electronics manufacturer aims to go nationwide with this undertaking this summer.